by The Canadian Press Posted Dec 28, 2012 5:20 pm MDT AddThis Sharing ButtonsShare to TwitterTwitterShare to FacebookFacebookShare to RedditRedditShare to 電子郵件Email Most actively traded companies on the TSX, TSX Venture Exchange markets TORONTO – Some of the most active companies traded Friday on the Toronto Stock Exchange and the TSX Venture Exchange:Toronto Stock Exchange (12,316.12 down 57.64 points):Poseidon Concepts Corp. (TSX:PSN). Oilfield services. Down 19 cents, or 12.84 per cent, at $1.29 on 6,598,377 shares. The Calgary-based company’s stock continued to drop, setting another record low a day after announcing it had suspended its dividend, replaced its CEO and initiated a board review of management and business processes.Research In Motion Ltd. (TSX:RIM). Wireless technology. Up five cents, or 0.43 per cent, at $11.75 on 3,665,059 shares. The BlackBerry maker sold its NewBay services subsidiary to Synchronoss Technologies for US$55.5 million. NewBay provides Internet services that allow customers to store and share content like photo albums and other data through smartphones, tablets and other devices.Cline Mining Corp. (TSX:CMK). Miner. Down 1.5 cents, or 18.75 per cent, at 6.5 cents on 3,645,897 shares.Iamgold Corp. (TSX:IMG). Miner. Down 11 cents, or 0.99 per cent, at $10.98 on 3,498,800 shares. The gold sector led all the decliners on the main index, shedding 0.72 per cent to 295.28 points.Uranium One Inc. (TSX:UUU). Miner. Up four cents, or 1.74 per cent, at $2.34 on 2,882,565 shares.Canadian Natural Resources Ltd. (TSX:CNQ). Energy. Down 10 cents, or 0.35 per cent, at $28.39 on 2,616,534 shares. The energy sector slipped 0.40 per cent to 246.03 points as the price of crude oil for February dipped seven cents to US$90.80 a barrel on the New York Mercantile Exchange.TSX Venture Exchange (1,201.84 up 5.09 points):Brilliant Resources Inc. (TSXV:BLT). Resource. Unchanged at 8.5 cents on 3,690,500 shares.Victoria Gold Corp. (TSXV:VIT) Gold. Down a penny, or 4.26 per cent, at 22.5 cents on 3,631,939 shares.Companies reporting major news:Canadian National Railway Co. (TSX:CNR). Railway. Down 59 cents, or 0.65 per cent, at $89.96 on 265,070 shares. The company reached a tentative labour agreement with about 700 signals and communications workers in Canada, represented by the International Brotherhood of Electrical Workers, System Council 11.South American Silver Corp. (TSX:SAC). Miner. Down two cents, or 7.14 per cent, at 26 cents on 134,159 shares. The Vancouver-based company bought a 19.9 per cent stake in High Desert Gold Corp. (TSXV:HDG) for $2.8 million. High Desert holds a 70 per cent interest in the Gold Springs gold project on the border between Utah and Nevada.